dis_accumulate.h
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#ifndef _RHEO_DIS_ACCUMULATE_H
#define _RHEO_DIS_ACCUMULATE_H
//
// This file is part of Rheolef.
//
// Copyright (C) 2000-2009 Pierre Saramito <Pierre.Saramito@imag.fr>
//
// Rheolef is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// Rheolef is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Rheolef; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
//
// =========================================================================
#include "rheolef/promote.h"
#include "rheolef/distributed.h"
#include <iterator>
namespace rheolef {
/*D:dis_accumulate
NAME: dis_accumulate - distributed accumulate algorithm (@PACKAGE@-@VERSION@)
DESCRIPTION:
STL-like accumulate for distributed containers
environment.
SYNOPSIS:
@example
template<class InputIterator, class Size>
T dis_accumulate (InputIterator first, Size n);
@end example
EXAMPLE:
A sample usage writes:
@example
# include "rheolef/disarray.h"
# include "rheolef/dis_accumulate.h"
int main(int argc, char**argv) {
environment distributed (argc, argv);
unsigned int n = 100;
disarray<double> x(n, 2.0);
double sum = dis_accumulate(x.begin(),x.size(),x.comm());
dout << "dot(x,1) = " << sum << endl;
}
@end example
SEE ALSO: "disarray"(1)
AUTHORS:
LMC-IMAG, 38041 Grenoble cedex 9, France
| Pierre.Saramito@imag.fr
DATE: 24 november 1998
End:
*/
template <class InputIterator, class Size>
typename std::iterator_traits<InputIterator>::value_type
dis_accumulate (
InputIterator first,
Size n,
const distributor::communicator_type& comm,
sequential /* memory_model */)
{
typedef typename std::iterator_traits<InputIterator>::value_type T;
T sum = T(0);
for (Size i = 0; i < n; ++i, ++first) {
sum = sum + (*first);
}
return sum;
}
#ifdef _RHEOLEF_HAVE_MPI
template <class InputIterator,class Size>
inline
typename std::iterator_traits<InputIterator>::value_type
dis_accumulate (
InputIterator first,
Size n,
const distributor::communicator_type& comm,
distributed /* memory_model */)
{
typedef typename std::iterator_traits<InputIterator>::value_type T;
T local_sum = dis_accumulate (first, n, comm, sequential());
return mpi::all_reduce (comm, local_sum, std::plus<T>());
}
#endif // _RHEOLEF_HAVE_MPI
template <class InputIterator, class Size>
inline
typename std::iterator_traits<InputIterator>::value_type
dis_accumulate (
InputIterator first,
Size n,
const distributor::communicator_type& comm)
{
return dis_accumulate (first, n, comm, rheo_default_memory_model());
}
} // namespace rheolef
#endif // _RHEO_DIS_ACCUMULATE_H
rheolef::distributor::communicator_type
communicator communicator_type
Definition: distributor.h:72
rheo_default_memory_model
#define rheo_default_memory_model
Definition: distributed.h:113
T
Expr1::float_type T
Definition: field_expr.h:261
mkgeo_ball.n
int n
Definition: mkgeo_ball.sh:150
rheolef
This file is part of Rheolef.
Definition: compiler_eigen.h:37
rheolef::dis_accumulate
std::iterator_traits< InputIterator >::value_type dis_accumulate(InputIterator first, Size n, const distributor::communicator_type &comm, sequential)
Definition: dis_accumulate.h:61
rheolef::distributed
Definition: distributed.h:88
rheolef::sequential
Definition: distributed.h:28